[rturben]

A lot of people in this thread are questioning how this adds any new information about time or how it is different/better than a classical explanation of systems (coffee cup reaching equilibrium based on thermodynamic laws).

One way that this result makes sense to me is by considering the properties of light speed and "spooky action at a distance." Particles become entangled with one another at the speed of light -- photons or fields carrying the information between the two. Looking at this from the perspective of light speed, there has been an instantaneous change between the two particles. State A has led directly to a more complicated, entangled State B. Still looking at this from light speed, there is no time between the transition from one state to the next and from that one to the next and so on. The universe has already worked itself out from the initial disentangled state to all the states that are increasingly more entangled.

Thanks to Einstein, we know that all objects try to move at light speed, but that the more massive they are the slower they become. Because we are massive objects, we don't experience time instantaneously like the photons do. We see the propagation of entanglement and see the state transitions. Our massiveness has given rise to a direction of time, the order that we understand the states of the universe to be proceeding in. Unlike light, we have to experience all the intermediate states in the order of less entangled -> more entangled. Thus an arrow of time.

This is already subtly bundled up in the classical explanations. Coffee cools off because it reaches equilibrium. Classical physics says this is because the particles in the coffee are hotter than the surrounding air, so it is more likely for those particles to break free of the coffee, thereby reducing its average kinetic motion. Consider though how those particles are interacting with one another. They don't just "know" the direction they're supposed to go, they bump into each other's fields and communicate at light speed. Each particle informs the next and as they become more entangled and learn more about where they are, they progress from state to state.